Vehicle trajectory modification for following

ABSTRACT

Techniques for determining to modify a trajectory based on an object are discussed herein. A vehicle can determine a drivable area of an environment, capture sensor data representing an object in the environment, and perform a spot check to determine whether or not to modify a trajectory. Such a spot check may include processing to incorporate an actual or predicted extent of the object into the drivable area to modify the drivable area. A distance between a reference trajectory and the object can be determined at discrete points along the reference trajectory, and based on a cost, distance, or intersection associated with the trajectory and the modified area, the vehicle can modify its trajectory. One trajectory modification includes following, which may include varying a longitudinal control of the vehicle, for example, to maintain a relative distance and velocity between the vehicle and the object.

BACKGROUND

Planner systems utilize information associated with objects in anenvironment to determine how to traverse the environment. For example,some existing planner systems consider relative positions to suchobjects to determine how to traverse the environment. Planner systemsmay also incorporate simple physics-based modeling to predict futurestates of such objects when determining how to traverse the environment.

BRIEF DESCRIPTION OF THE DRAWINGS

The detailed description is described with reference to the accompanyingfigures. In the figures, the left-most digit(s) of a reference numberidentifies the figure in which the reference number first appears. Theuse of the same reference numbers in different figures indicates similaror identical components or features.

FIG. 1 is a schematic diagram illustrating an example implementation ofdetermining whether to follow an object, as described herein.

FIG. 2 is a schematic diagram illustrating another exampleimplementation of determining whether to follow an object, as describedherein.

FIGS. 3 and 4 are schematic diagrams illustrating exampleimplementations of determining whether to follow an object, as describedherein.

FIG. 5 is a block diagram illustrating an example computing system forgenerating a drivable area, as described herein.

DETAILED DESCRIPTION

Techniques described herein are directed to determining, for anautonomous vehicle (hereinafter “vehicle”), whether to follow an object.Such a determination may include determining whether an object is orwill be within a threshold distance of the vehicle at a point along atrajectory generated by the vehicle. For example, the vehicle cangenerate a drivable area representing a region of the environment inwhich the vehicle can traverse. The vehicle can capture sensor data ofthe environment, which may represent an object such as another vehiclein an adjacent lane or otherwise proximate to the vehicle. The drivablearea can be updated to reflect a current or predicted position of theobject, and the operations can include determining, for various pointsalong the trajectory generated by the vehicle, whether the current orpredicted location of the object is within a threshold distance of thetrajectory. If the object encroaches on the trajectory (e.g., based ondistance threshold(s) and/or cost(s)), the vehicle can determine tofollow the object. Following may involve varying longitudinal controlsof the vehicle (e.g., velocity and/or acceleration) to maintain aminimum distance between the vehicle and the object, wherein the minimumdistance may be based, at least in part, on a relative distance and/orvelocity between the vehicle and the object.

An object may, for example, be located in or relatively near a drivablearea in which the autonomous vehicle can travel in an environment. In anexample, the object may be just beginning to merge from an adjacent laneinto the lane of the drivable area.

In various implementations, the vehicle may perform a “spot check” ofone object at a time to determine whether or not to follow one of theobjects. Such a spot check may be a relatively fast process by generallyavoiding additional use of a processor for more detailed calculations,such as those involving predicting motions of the one or more objects,determining possible trajectories based on the predicted motions, and soon. Instead, a spot check may involve individually considering (e.g.,“fusing” in) one object at a time with respect to the drivable area. Foreach such object, a reference trajectory (e.g., a lateral plan of thecurrent or latest trajectory) may be checked (e.g., considered orcompared) against a computed candidate drivable area. As noted above, ifthe reference trajectory intersects the candidate drivable area or iswithin a threshold distance of a boundary of the candidate drivable area(or, in other embodiments, a cost associated with the newly computedcandidate drivable area is relatively high), the vehicle may choose tofollow the object. In this case of following, the newly computedcandidate drivable area can be used to subsequently modify thetrajectory. On the other hand, in the case of no intersection and thusno following, the newly computed candidate drivable area is used merelyas a “spot check” measurement and subsequently discarded. Such spotchecks of each individual object in an environment may subsequently beused to inform a controller.

Based on a decision of whether to follow the object, a computing deviceof the autonomous vehicle may determine to construct and subsequentlymodify the drivable area by considering a plurality of various dynamicand/or static objects and/or predictions of how such objects willoperate in the environment. A non-limiting list of objects may includeobstacles in an environment, including but not limited to pedestrians,animals, cyclists, trucks, motorcycles, other vehicles, or the like. Inat least one example, a drivable area is a virtual representation in theenvironment that generally defines the constraints and/or boundarieswithin which a vehicle can safely travel relative to the objects andobstacles to effectively reach an intended destination. In someexamples, the drivable area is determined by computing device(s) on anautonomous vehicle and can be utilized by those computing device(s) tonavigate the autonomous vehicle in the environment. That is, thecomputing device(s) onboard the autonomous vehicle can determinetrajectories based on the extents of the drivable area.

Generally, a drivable area may be determined as a virtual space in theenvironment in which the vehicle can travel. The drivable area mayinclude boundaries that provide offsets from the objects, which may bedetermined based on semantic properties of the object(s), probabilisticmodels (including models of the motion of objects, sensor measurements,and the like), rules of the road (e.g., incorporating lane boundaries,sidewalks, and the like) or other information. In at least someexamples, discrete portions (e.g., every 10 cm, 50 cm, 1 m, etc.) alongthe drivable area boundaries may be encoded with additional information,such as, but not limited to, distance to the nearest object, semanticclassification of the nearest object, uncertainties (e.g., based onsensor noise), confidences, etc. Moreover, in some implementations, morethan one drivable area may be determined. For example, much like realworld drivers may have multiple options for avoiding an object, e.g.,pass on the right or pass on the left on a three-lane road, multipledrivable areas may be determined for more than one potential plannedpath. In these examples, one drivable area is selected forimplementation. For example, a drivable area may be preferred because ithas a larger area, because it better conforms to traffic laws (e.g.,pass a vehicle on the left instead of the right), because it avoids themost objects, or for one or more additional reasons.

As a non-limiting example, a computing device of an autonomous vehiclemay receive sensor data and detect one or more objects in an environmentand/or determine attributes or object parameters of the one or moreobjects in the environment. Object parameters may comprise velocity,acceleration, position, classification, and/or extents of each of theone or more objects, in addition to any uncertainty informationassociated therewith. Sensor data captured by the autonomous vehicle mayinclude light detection and ranging (LIDAR) sensor data, radio detectionand ranging (RADAR) sensor data, sound navigation and ranging (SONAR)sensor date, image data, time of flight data, and the like. In somecases, sensor data may be provided to a perception system configured todetermine a type of object (e.g., vehicle, pedestrian, bicycle, animal,parked car, tree, building, and the like) in the environment. Further,the perception system can determine, based on the sensor data, movementinformation about the object in the environment.

In some instances, the computing device of the autonomous vehicle canutilize the object(s) and/or the attributes of the object(s) todetermine which object(s) should be considered when determining adrivable area, to determine extents of the drivable area, and/or todetermine a trajectory, or modify an existing trajectory, to navigatethe autonomous vehicle in the drivable area. In some examples, whetherto modify a drivable area and/or trajectory can be determined, at leastin part, by considering one or more costs and/or constraints associatedwith vehicle dynamics of a predicted trajectory.

In some implementations, the computing device(s) on an autonomousvehicle may determine, or modify, a drivable area by fusing or includingdata about a number of objects in the environment. For example, thecomputing device(s) may determine a trajectory that navigates throughthe environment relative to one or more objects. At discrete points (orline segments at discrete points) along the trajectory, the computingdevice(s) may then determine lateral distances (for example) from thetrajectory to the objects. For example, the computing device(s) may useray casting techniques to determine the lateral distances at poses of avehicle along the trajectory. Based on these distances and informationabout the object(s), a modified trajectory may then be determined. Forexample, the computing device(s) may use semantic information about theobjects to classify the objects and determine a safety factor or safetylevel associated therewith. In some instances, a minimum offset distanceof the vehicle from an object, or a safety margin, may be associatedwith each safety level. The computing device(s) may also useprobabilistic information about the objects to determine the safetylevel and/or the offset distance of the vehicle relative to the object.For instance, the computing device(s) may apply probabilistic filteringto the distance determinations, for example, to account for uncertaintyassociated with the lateral distances. For instance, uncertainty may beassociated with the measurements, e.g., with calibration and/ortolerances of sensors and/or sensor components, with motion of thesensed objects, e.g., uncertainty associated with potential futuremovement of objects or prediction models that characterize the movement,or the like.

In some implementations, a cost or constraint may be used, for example,to enforce safe driving conditions and/or physical correctness (e.g., toensure that a trajectory follows a physically plausible trajectory). Insome cases, a trajectory can be determined by interpolating betweenpoints, which are determined by processes described below, or fitting acurve to the points (e.g., fitting one or more of a polynomial curve, aBezier curve, a clothoid curve, etc.). In some cases, generating ormodifying a trajectory and/or selecting the points can be based at leastin part on one or more costs and/or constraints associated with vehicledynamics to prevent or reduce an occurrence where the trajectory couldlead to risky or unsafe driving conditions or represents an unreasonabletrajectory (e.g., involving “teleportation” of the vehicle wheresubsequent points comprise physically impossible motion of the vehicle).Examples of such costs may include, but are not limited to, a velocitycost (e.g., a constant velocity cost), an acceleration cost, anexpectation that the object may follow rules of the road, and the like.

For example, generally a drivable area (e.g., drive corridor/envelope)is determined based on objects in the environment. In some examples,such objects may represent static objects (e.g., parked cars, buildings,pylons, etc.). In other examples, such objects may additionally, oralternatively, include dynamic objects which would not impact drivingwithin a lane (e.g., vehicles behind the autonomous vehicle, oncomingvehicles, and the like). A trajectory constrained to the drivable areais subsequently generated. In response to an object (e.g., a secondvehicle in an adjacent lane) entering the drivable area of the vehicle(and/or a prediction of such an event), the drivable area may bemodified in a “spot-checking” operation. A comparison (e.g., via thespot check) between the modified (e.g., most-updated) drivable area andthe latest trajectory may determine whether the object is to be followedor not. In the case of a determination to follow, the trajectory may bemodified based on the comparison. Otherwise, the trajectory need not bemodified, at least not in response to the action of the object thus far.In other words, if the object is not to be followed, the drivable areaand/or trajectory may be maintained and the vehicle will continue on thecurrent trajectory.

In some examples, once a modified drivable area is established, thecomputing device of the autonomous vehicle may determine whether togenerate one or more new trajectories for proceeding within the drivablearea. Thus, for example, the drivable area may define boundaries of aregion in which the vehicle may travel, and the trajectories may bediscrete segments within the drivable area according to which thevehicle will travel. Thus, for example, while the drivable area may becalculated using a planned path through the environment, thetrajectories may be discrete, shorter segments intended to be carriedout by the vehicle to traverse through the environment, within thedrivable area.

Techniques described herein are directed to leveraging sensor andperception data to enable a vehicle, such as an autonomous vehicle, tonavigate through an environment while following or circumventing objectsin the environment. For example, one or more trajectories can begenerated based on prediction probabilities and such trajectories may beprovided to a planner system to control an operation of the autonomousvehicle

In some examples, a prediction system of a computing device of theautonomous vehicle can include a machine learning model trained tooutput data that can be used to generate one or more predictedtrajectories of objects proximate to the autonomous vehicle. Forexample, the machine learning model can output coordinates (e.g.,x-coordinates and y-coordinates) associated with the object (e.g., athird-party vehicle) at one or more times in the future (e.g., 1 second,2 seconds, 3 seconds, etc.). In some examples, the machine learningmodel can output coordinates associated with the object as well asprobability information associated with each coordinate. In someexamples, such probability information can be represented as an ellipseor other polygon associated with a threshold probability level (e.g., a65% probability that a location of the object at a particular time iswithin the area represented by the ellipse). A predicted trajectory canbe generated by interpolating between the coordinates output by themachine learning model. In some examples, the machine learning model caninclude a convolutional neural network (CNN), which may include one ormore recurrent neural network (RNN) layers, such as, but not limited to,long short-term memory (LSTM) layers. In some examples, the machinelearning model can output a heat map associated with predictionprobabilities. In some examples, at least one predicted trajectory canbe determined based at least in part on the heat map.

Techniques described herein can provide a robust framework fordetermining whether to follow an object in an environment. Techniquesdescribed herein may be faster than conventional techniques byperforming a geometric or cost-based check based on incorporating objectextents into the drivable area of the vehicle. In some cases, quicklydetermining to follow a vehicle may allow a planning system to alter atrajectory of the vehicle (e.g., by slowing down) which may improvesafety outcomes (e.g., by maintaining a minimum distance between thevehicle and the object) and/or by improving passenger comfort (e.g., byslowly decelerating rather than braking to adjust a velocity of thevehicle)

The techniques described herein can be implemented in a number of ways.Example implementations are provided below with reference to thefollowing figures. Although discussed in the context of an autonomousvehicle, the methods, apparatuses, and systems described herein can beapplied to a variety of systems (e.g., a sensor system or a roboticplatform), and are not limited to autonomous vehicles. In anotherexample, the techniques can be utilized in an aviation or nauticalcontext. Additionally, the techniques described herein can be used withreal data (e.g., captured using sensor(s)), simulated data (e.g.,generated by a simulator), or any combination of the two.

FIGS. 1-5 provide additional details associated with techniquesdescribed herein.

FIG. 1 is a pictorial flow diagram showing example processes involvedduring a determination of whether or not a vehicle is to follow anobject, as described herein. Specifically, FIG. 1 illustrates a process100 performed by a vehicle 102 in which an object 104 in an environmentis considered in a determination of whether to create modified controlsfor the vehicle. In the specific example, object 104, such as a vehicle,may be in an adjacent lane and merging into the path or lane of vehicle102. This situation, among others, may lead to a determination as towhether or not to follow object 104. A modified drivable area maysubsequently be used to determine and/or modify a trajectory through theenvironment, e.g., so vehicle 102 can travel through the environmentalong the trajectory. A modified trajectory is associated with vehicle102 following object 104 while an unmodified trajectory is associatedwith not following object 104. In an example where the object 104 isdirectly in front of vehicle 102, the drivable area is modified so thatthe drivable area does not include object 104, and a resulting modifiedtrajectory would lead to vehicle 102 following object 104.

The processes illustrated in FIG. 1 are not limited to being performedusing vehicle 102 and can be implemented using any of the other vehiclesdescribed in this application, as well as vehicles other than thosedescribed herein. Moreover, vehicle 102 described herein is not limitedto performing the processes illustrated in FIG. 1.

Process 100 is illustrated as collections of blocks in logical flowgraphs, which represent sequences of operations that can be implementedin hardware, software, or a combination thereof. In the context ofsoftware, the blocks represent computer-executable instructions storedon one or more computer-readable storage media that, when executed byprocessor(s), perform the recited operations. Generally,computer-executable instructions include routines, programs, objects,components, data structures, and the like that perform particularfunctions or implement particular abstract data types. The order inwhich the operations are described is not intended to be construed as alimitation, and any number of the described blocks can be combined inany order and/or in parallel to implement the processes. In someembodiments, one or more blocks of the process can be omitted entirely.Moreover, process 100 can be combined in whole or in part with otherprocesses.

At block 106, vehicle 102, via operations implemented in hardware,software, or a combination thereof, determines a drivable area and atrajectory in an environment. The drivable area may have been previouslydetermined based on positions/locations of one or more static obstacles(e.g., lane boundaries, curbs, sidewalks, parked cars, etc.) and/ordynamic obstacles (e.g., oncoming traffic, etc.) in the environment. Asillustrated, vehicle 102 is following a trajectory 108 in a drivablearea 110. Vehicle 102 is travelling in a lane 112 and object 104 (e.g.,another vehicle) is travelling in an adjacent lane 114. The two lanesare bounded by a partition 116, which may be a paint stripe or Botts'dots (e.g., raised pavement markers), though partition 116 need notcomprise any markers in some implementations. Drivable area 110 may begenerated based on static and/or dynamic objects in the environment. Insome implementations, the size and geometry of drivable area 110 may bedetermined (and resultingly may include “cut-outs” (not illustrated inFIG. 1) that are areas removed from drivable area 110) based onconsiderations of special objects in the environment, such asemergency-response vehicles, oncoming traffic, crossing traffic, and soon. In other words, such special objects may dictate that various partsof drivable area otherwise determined based on other objects are notacceptable and should be removed for the “final” version of the drivablearea.

At block 118, vehicle 102, via operations implemented in hardware,software, or a combination thereof, determines a modified drivable areabased on actions and/or position of object 104. Such a determination maybe based on sensor data associated with object 104 and received byvehicle 102. In the example situation depicted in FIG. 1, object 104performs an action of changing, drifting, and/or merging into lane 114from lane 112, resulting in a lane intrusion. This action may promptvehicle 102 to determine a modified drivable area 110*, which mayinclude a “cut-out” or removal of a portion 120 of drivable area 110. Inother implementations, vehicle 102 may determine a modified drivablearea 110* in response to merely the proximity of object 104 to vehicle102, regardless of the action of object 104. In yet otherimplementations, described below, vehicle 102 may determine a modifieddrivable area 110* based, at least in part, on costs associated withobject 104. In still other implementations, described below, vehicle 102may determine a modified drivable area 110* based, at least in part, onpredicted behavior of object 104. The process of block 118 may beperformed one at a time for additional nearby objects (not illustratedin FIG. 1).

As described below, vehicle 102 can include a sensor system(s) such asLIDAR sensors, RADAR sensors, ultrasonic transducers, SONAR sensors,time of flight sensors, location sensors (e.g., GPS, compass, etc.),inertial sensors (e.g., inertial measurement units, accelerometers,magnetometers, gyroscopes, etc.), cameras (e.g., RGB, IR, intensity,depth, etc.), microphones, wheel encoders, environment sensors (e.g.,temperature sensors, humidity sensors, light sensors, pressure sensors,etc.), etc. A sensor system(s) can provide input to vehicle computingdevice(s) and one or more systems of vehicle computing device(s) canutilize the input. For instance, in at least one example, vehiclecomputing device(s) can receive the input for processing by alocalization system, perception system, prediction system, plannersystem, and/or drivable area determination system.

In at least one example, vehicle 102 can send sensor data to computingdevice(s) via network(s). In some examples, vehicle 102 can send rawsensor data to computing device(s). In other examples, vehicle 102 cansend processed sensor data and/or representations of sensor data tocomputing device(s) (e.g., data output from a localization system,perception system, prediction system, and/or planner system). In someexamples, vehicle 102 can send sensor data to computing device(s) at aparticular frequency, after a lapse of a predetermined period of time,in near real-time, etc. Sensor data collected over time can correspondto log data.

At block 122, vehicle 102, via operations implemented in hardware,software, or a combination thereof, evaluates the trajectory of vehicle102 based on the modified drivable area. In some cases, the operationsmay include evaluating at discrete timesteps or points along thetrajectory 108 a state of the environment, which may be referred to as a“rollout”. Such evaluating may include updating a position of thevehicle 102 and/or the object 104 as anticipated over time. Such anevaluation is part of a technique for determining whether object 104affects the trajectory by determining whether the modified drivablearea, based on object 104, requires a new trajectory. For example, ifobject 104 moves substantially into lane 112, drivable area 110 wouldneed to be modified. Even in this situation, trajectory 108 may not haveto be modified if, for instance, there remains a lateral clearance 124that is safe and significant (e.g., with respect to a threshold valuebased on a velocity of the vehicle 102 and/or the object 104, aclassification of the object 104, location of the vehicle 102 in a map,and the like) between trajectory 108 and object 104. In this case,vehicle 102 may pass object 104 (or otherwise continue following thetrajectory 108), thus choosing not to follow object 104.

At block 126, vehicle 102 determines whether to modify control(s)associated with trajectory 108. For example, as described above, suchdetermining may be based on whether object 104 affects trajectory 108.In some examples, such a determination may be made geometrically (e.g.,does the trajectory 108 intersect a boundary of the drivable area 110and/or within a predetermined distance thereof). In additional, oralternate, examples, such a determination may comprise determiningvarious costs associated with following the trajectory given the updatedor modified drivable area 110*. For example, such costs may be based atleast in part on trip parameters associated with the trajectory. In someimplementations, trip parameters may comprise one or more of accidentrisk factors and vehicle dynamics (e.g., which may be used to determinea safe stop trajectory for safely and comfortably slowing down (orstopping)). Cost or trip parameters may also include data associatedwith minimum distances to maintain between the vehicle and the object.Other trip parameters may include vehicle dynamics, passenger comfort,estimated time of arrival, and energy usage, just to name a fewexamples.

At block 128, objects in addition to object 104 may be included andconsidered, one at a time (and/or substantially simultaneously andindependently), in blocks 118, 122, and 126 of process 100. In this way,information about each object may be fused or combined with drivablearea 110 individually and checked against a reference line (e.g.,trajectory 108) to determine whether or not to follow (e.g. controlaccording to a longitudinal velocity). As described above, a number ofobjects may be present in an environment in which an autonomous vehicleis travelling. Such objects may include vehicles and pedestrians. Basedon sensor data, vehicle computing devices may recognize the objects,e.g., via image processing, vision detection, classification and/orsegmentation, LIDAR detection, segmentation, and/or classification,and/or other processes.

At block 130, vehicle 102 is controlled based on modified control(s)associated with a modified trajectory so that vehicle 102 is followingobject 104. Alternatively, vehicle 102 is controlled based on unmodifiedcontrols associated with (unmodified) trajectory 108 so that vehicle 102is not following object 104.

FIG. 2 is a pictorial flow diagram showing example processes involvedduring a determination of whether or not a vehicle is to follow anobject based on predicted behavior of the object, as described herein.Specifically, FIG. 2 illustrates an environment similar to that of FIG.1, but another process 200 is performed by vehicle 102. Process 200includes determining whether to create a modified drivable area forvehicle 102 based on predictions of actions performed by object 104. Inthe specific example, object 104 may be in an adjacent lane and justbeginning (or demonstrating some indication of intent) to merge into thepath or lane of vehicle 102. This situation, among others, may lead to adetermination as to whether or not to follow object 104. A modifieddrivable area may subsequently be used to determine and/or modify atrajectory through the environment, e.g., so vehicle 102 can travelthrough the environment along the trajectory. A modified trajectory isassociated with vehicle 102 following object 104 while an unmodifiedtrajectory is associated with vehicle 102 not following object 104.

As for process 100 above, process 200 is illustrated as collections ofblocks in logical flow graphs, which represent sequences of operationsthat can be implemented in hardware, software, or a combination thereof.In the context of software, the blocks represent computer-executableinstructions stored on one or more computer-readable storage media that,when executed by processor(s), perform the recited operations.Generally, computer-executable instructions include routines, programs,objects, components, data structures, and the like that performparticular functions or implement particular abstract data types. Theorder in which the operations are described is not intended to beconstrued as a limitation, and any number of the described blocks can becombined in any order and/or in parallel to implement the processes. Insome embodiments, one or more blocks of the process can be omittedentirely. Moreover, process 200 can be combined in whole or in part withother processes.

At block 202, vehicle 102, via operations implemented in hardware,software, or a combination thereof, determines a drivable area and atrajectory in an environment. The drivable area may have been previouslydetermined based on positions/locations of one or more static or dynamicobstacles in the environment. As illustrated, vehicle 102 is following atrajectory 204 in a drivable area 206. Vehicle 102 is travelling in lane112 and object 104 (e.g., another vehicle) is travelling in adjacentlane 114. The two lanes are bounded by partition 116, which may be apaint stripe or Botts' dots (e.g., raised pavement markers), thoughpartition 116 need not comprise any markers in some implementations.Drivable area 206 may be generated based on static and/or dynamicobjects in the environment.

At block 208, vehicle 102, via operations implemented in hardware,software, or a combination thereof, determines a predicted trajectoryassociated with object 104. A predicted motion of the object may be usedto determine a likelihood that object 104 will cut in front of vehicle102, which could affect and/or potentially interfere with operation ofvehicle 102. For example, a lane change by object 104 may requirevehicle 102 to decelerate to make room for object 104 to follow theobject. This situation would involve modifying drivable area 206 ofvehicle 102. In particular, at block 210, vehicle 102, via operationsimplemented in hardware, software, or a combination thereof, determinesa modified drivable area based on the predicted trajectory of object104. In the example situation depicted in FIG. 2, vehicle 102 predicts atrajectory 212 from a predicted likelihood (which, for example, mayexceed a predetermined threshold) that object 104 will drift and/ormerge into lane 114 from lane 112, resulting in a lane intrusion. Thispredicted trajectory of object 104 may prompt vehicle 102 to determine amodified drivable area 206*, which may include a “cut-out” or removal ofa portion 214 of drivable area 206. In some implementations, vehicle 102may determine a plurality of predicted trajectories for object 104, andeach one of these predicted trajectories may be associated with alikelihood value. Vehicle 102 may determine a modified drivable area206* based on the predicted trajectory having the highest likelihoodvalue, for example (e.g., in those examples where multiple predictedtrajectories for such an object are determined), though any predictedtrajectory may be used and/or an uncertainty or probability of such atrajectory. The process of blocks 208 and 210 may be performed one at atime for additional nearby objects (not illustrated in FIG. 2) and/orsubstantially simultaneously and independently.

Vehicle 102 may predict behavior of object 104 (and other objects) basedon data gathered by a sensor system(s) such as that described above.Such a sensor system(s) can provide input to vehicle computing device(s)and one or more systems of vehicle computing device(s) can utilize theinput. For instance, in at least one example, vehicle computingdevice(s) can receive the input for processing by a localization system,perception system, prediction system, planner system, and/or drivablearea determination system.

At block 216, vehicle 102, via operations implemented in hardware,software, or a combination thereof, evaluates trajectory 204 of vehicle102 based on the modified drivable area 206* (which in turn may havebeen modified based on predicted trajectory 212 of object 104). In somecases, the operations may include evaluating at discrete timesteps orpoints along the trajectory 204 a state of the environment, which may bereferred to as a “rollout”. Such evaluating may include updating aposition of the vehicle 102 and/or the object 104 as anticipated overtime (e.g., based on controls associated with the vehicle 102 and/orbased on expected positions, accelerations, velocities, etc. associatedwith the predicted trajectory 204). Such an evaluation is part of atechnique for determining whether object 104 affects trajectory 204 bydetermining whether the modified drivable area 206*, based on object104, requires a new trajectory (e.g., to replace trajectory 204). Forexample, if predicted trajectory 212 of object 104 intersects or comeswithin a predetermined threshold distance of trajectory 204 of vehicle102, then the trajectory 204 and/or the drivable area 206 would need tobe modified. In additional or alternative examples, costs associatedwith the trajectory 204 with respect to the modified drivable area 206*may be determined.

At block 218, vehicle 102 determines whether to modify control(s) ofvehicle 102 associated with trajectory 204. For example, as describedabove, such determining may be based on whether object 104 affectstrajectory 204. In the example depicted in FIG. 2, predicted trajectory212 of object 104 leads to object 104 being directly in front of vehicle102 and, in some timesteps, occupying a portion of the environmentassociated with the trajectory 204. This situation may result in vehicle102 generating a modified trajectory 220 (e.g., which replacestrajectory 204), to follow object 104.

As in FIG. 1, such a determination may be made with respect to geometry(whether the trajectory 204 intersects and/or comes within a thresholddistance of the modified drivable area 206*) and/or by reevaluatingvarious costs associated with the modified drivable area 206*. Forexample, such costs may be based at least in part on trip parametersassociated with the trajectory. In some implementations, trip parametersmay comprise one or more of functions of distances to boundaries (e.g.,parabolic, polynomial, exponential, etc.), vehicle speed, changes invehicle acceleration, following distances, accident risk factors andvehicle dynamics (e.g., which may be used to determine a safe stoptrajectory for safely and comfortably slowing down (or stopping)), andthe like. Cost or trip parameters may also include data associated withminimum distances to maintain between the vehicle and the object. Othertrip parameters may include vehicle dynamics, passenger comfort,estimated time of arrival, and energy usage, just to name a fewexamples.

At block 222, vehicle 102 is controlled based on modified controlsassociated with a modified trajectory so that vehicle 102 is followingobject 104. Alternatively, in the case where predicted trajectory 212 ofobject 104 does not intersect or interfere with trajectory 204 ofvehicle 102, vehicle 102 is controlled based on unmodified controlsassociated with (unmodified) trajectory 108 so that vehicle 102 is notfollowing object 104.

As will be appreciated, as vehicle 102 moves through the environment,objects in the environment are ever-changing. Accordingly, processes 100and 200 may be carried out iteratively. For example, new drivable areasmay be determined in near real-time, e.g., at intervals of from about0.5 seconds to about 3 seconds or so. Moreover, as objects changepositions, velocities, attitudes, and the like, relative to the vehicle,the drivable area can be updated to include new information about theobject. Moreover, each drivable area may be based on a propagation ofpredicted motion, e.g., of the vehicle and/or of the object(s). Thus,for example, the position along the path at which the lateral distancesare determined may include an approximation of where objects will bewhen the vehicle is at a position associated with a trajectory.

FIG. 3 is a schematic diagram illustrating an example implementation 300of a vehicle 302 at an intersection determining whether to follow anobject 304. Specifically, FIG. 3 illustrates vehicle 302 behind (e.g.,following) object 304, both travelling in a lane 306 and approaching anintersection. As depicted in the figure, object 304 is turning left intoa lane 308 of an intersecting street. Prior to the depicted situation,vehicle 302 may have been behind object 304 for a while or,alternatively, object 304 may have just entered lane 306 from a rightlane 308 preparing to make the left turn, thus pulling in front of(e.g., cutting off) vehicle 302. Such a turn may lead to two, amongother, situations. In a first situation, for example, object 304 maysubstantially slow down or stop during or prior to making the turn fromlane 306 to lane 308. In a second situation, object 304 maysubstantially maintain its speed during the complete process of theturn. In either situation, vehicle 302 may perform a process ofdetermining whether or not to follow object 304 up until object 304turns. For example, in the first situation, an action of followingobject 304 implies that vehicle 302 slows down concomitant with theslowing down of object 304, so that a safe distance between the vehicleand object is maintained. Alternatively, in the first situation, anaction of not following object 304 implies that vehicle 302 passesobject 304 via right lane 310. In the second situation, an action offollowing object 304 implies that vehicle 302 maintains its speed withthe expectation that the object 304 may turn out of the lane 306 to thelane 308. Alternatively, in the second situation, an action of notfollowing object 304 implies that vehicle 302 passes object 304 via aright lane 310.

In various implementations, vehicle 302 may perform a “spot check” ofobject 304 to determine whether or not to follow the object. Asdescribed above, such a spot check may be a relatively fast process bygenerally avoiding additional use of a processor for more detailedcalculations, such as those involving determining detailed cost(s) orpredicting motions of the object, determining possible trajectoriesbased on the predicted motions, and so on. Instead, the spot check mayinvolve evaluating and comparing a lateral plan of the current or latesttrajectory 312 of a drivable area 314 of vehicle 302 against atrajectory of a newly computed modified drivable area of vehicle 302.Note that drivable area 314 is indicative of the latter situation above,where object 304 has suddenly pulled in front of vehicle 302. If thereference trajectory 312 intersects (or, in other embodiments, a costassociated with the such a trajectory with reference to the newlycomputed modified drivable area is relatively high), vehicle 302 maychoose to follow object 304. In this case of following, the newlycomputed modified drivable area 314 is used to modify the trajectory ofvehicle 302. On the other hand, in the case of no intersection and thusno following, the newly computed candidate drivable area is used merelyas a “spot check” measurement and subsequently discarded. In someimplementations, vehicle 302 may modify drivable area 314 based on apredicted trajectory 316 of object 304, as described above.Alternatively, if the vehicle 302 determines that the object 304 willturn out of the lane 306 into lane 308, the vehicle 302 may maintain avelocity which may reduce a distance between the vehicle 302 and theobject 304 which might otherwise be associated with a “brake tap” toslow the vehicle 302 down. That is, in some cases, determining that theobject 304 may turn out of a drivable area 314 based on a predictedtrajectory 316 may reduce decelerations, thereby improving ride comfortand/or conserving vehicle energy resources.

FIG. 4 is a schematic diagram illustrating an example implementation 400of a vehicle 402 at an intersection determining whether to follow anobject 404. Specifically, FIG. 4 illustrates vehicle 402 travelling in alane 406 and approaching an intersection. As depicted in the figure,object 404 is in an oncoming lane 408 and turning right onto a lane 410of the intersecting street. Vehicle 402 is also intending to turn intolane 410 (from lane 406). Such turns by vehicle 402 and object 404 maylead to two, among other, situations. In a first situation, for example,object 404 may substantially slow down or stop during or prior to makingthe turn from lane 408 to lane 410. In a second situation, object 404may substantially maintain its speed during the complete process of theturn. In either situation, vehicle 402 may perform a process ofdetermining whether or not to follow object 404 subsequent to turning.For example, in the first situation, an action of following object 404implies that vehicle 402 slows down enough to allow object 404 to turnbefore vehicle 402 turns. And subsequent to both turns (of object 404and of vehicle 402), following implies that a safe distance between thevehicle and object is maintained in lane 410. Alternatively, in thefirst situation, an action of not following object 404 implies thatvehicle 402 does not yield to object 404 and turns onto lane 410 beforeobject 404 turns onto lane 410. In the second situation, an action offollowing object 404 implies that vehicle 402 proceeds with the turn andmaintains a safe distance behind object 404 in lane 410.

In various implementations, vehicle 402 may perform a spot check ofobject 404 to determine whether or not to follow the object. The spotcheck may involve evaluating and comparing a lateral plan of the currentor latest trajectory 412 of vehicle 402 against a newly computedmodified drivable area of vehicle 402. If the reference trajectoryintersects (or, in other embodiments, a cost associated with the newlycomputed modified drivable area is relatively high), vehicle 402 maychoose to follow object 404. In this case of following, the newlycomputed modified drivable area is used to modify the trajectory ofvehicle 402. On the other hand, in the case of no intersection and thusno following, the newly computed candidate drivable area is used merelyas a “spot check” measurement and subsequently discarded. In someimplementations, vehicle 402 may modify drivable area 414 based on apredicted trajectory 416 of object 404, as described above.

FIG. 5 is a block diagram illustrating an example system 500 forgenerating and utilizing a drivable area as described herein. In atleast one example, system 500 can include a vehicle 502, which can bethe same vehicle as vehicles 102, 302, and 402 described above withreference to FIGS. 1-4. Vehicle 502 can include one or more vehiclecomputing devices 504, one or more sensor systems 506, one or moreemitters 508, one or more communication connections 510, at least onedirect connection 512, and one or more drive systems 514. In at leastone example, sensor system(s) 506 can correspond to sensor systemsdescribed above.

Vehicle computing device(s) 504 can include processor(s) 516 and memory518 communicatively coupled with processor(s) 516. In the illustratedexample, vehicle 502 is an autonomous vehicle. However, vehicle 502could be any other type of vehicle. In the illustrated example, memory518 of vehicle computing device(s) 504 stores a localization system 520,a perception system 522, a prediction system 524, a planner system 526,a drivable area determination system 528, and one or more systemcontrollers 530. Although these systems and components are illustrated,and described below, as separate components for ease of understanding,functionality of the various systems and controllers may be attributeddifferently than discussed. By way of non-limiting example,functionality attributed to perception system 522 may be carried out bylocalization system 520 and/or prediction system 524. Moreover, fewer ormore systems and components may be utilized to perform the variousfunctionalities described herein. Furthermore, though depicted in FIG. 5as residing in memory 518 for illustrative purposes, it is contemplatedthat localization system 520, perception system 522, prediction system524, planner system 526, drivable area determination system 528, and/orone or more system controllers 530 can additionally, or alternatively,be accessible to vehicle 502 (e.g., stored on, or otherwise accessibleby, memory remote from vehicle 502).

As also illustrated in FIG. 5, memory 518 can include a map storage 532,which may store one or more maps, and/or object information storage 534,which may store object information. A map can be any number of datastructures modeled in two dimensions or three dimensions that canprovide information about an environment, such as, but not limited to,topologies (such as intersections), streets, mountain ranges, roads,terrain, and the environment in general.

In at least one example, localization system 520 can includefunctionality to receive data from sensor system(s) 506 to determine aposition and/or orientation of vehicle 502 (e.g., one or more of an x-,y-, z-position, roll, pitch, or yaw). For example, localization system520 can include and/or request/receive a map of an environment (e.g.,from map storage 532) and can continuously determine a location and/ororientation of the autonomous vehicle within the map. In some instances,localization system 520 can utilize SLAM (simultaneous localization andmapping), CLAMS (calibration, localization and mapping, simultaneously),relative SLAM, bundle adjustment, non-linear least squares optimization,differential dynamic programming, or the like to receive image data,LIDAR data, RADAR data, IMU data, GPS data, wheel encoder data, and thelike to accurately determine a location of the autonomous vehicle. Insome instances, localization system 520 can provide data to variouscomponents of vehicle 502 to determine an initial position of anautonomous vehicle for generating a trajectory for travelling in theenvironment.

In some instances, perception system 522 can include functionality toperform object detection, segmentation, and/or classification. In someexamples, perception system 522 can provide processed sensor data thatindicates a presence of an object that is proximate to vehicle 502, suchas objects 104, 304, and 404. The perception system may also include aclassification of the entity as an entity type (e.g., car, pedestrian,cyclist, animal, building, tree, road surface, curb, sidewalk, unknown,etc.). For instance, perception system 522 may compare sensor data toobject information in object information database 534 to determine theclassification. In additional and/or alternative examples, perceptionsystem 522 can provide processed sensor data that indicates one or morecharacteristics associated with a detected object and/or the environmentin which the object is positioned. In some examples, characteristicsassociated with an object can include, but are not limited to, anx-position (global and/or local position), a y-position (global and/orlocal position), a z-position (global and/or local position), anorientation (e.g., a roll, pitch, yaw), an object type (e.g., aclassification), a velocity of the object, an acceleration of theobject, an extent of the object (size), a bounding box associated withthe object, etc. Characteristics associated with the environment caninclude, but are not limited to, a presence of another object in theenvironment, a state of another object in the environment, a time ofday, a day of a week, a season, a weather condition, an indication ofdarkness/light, etc.

Prediction system 524 can access sensor data from sensor system(s) 506,map data from map storage 532, and, in some examples, perception dataoutput from perception system 522 (e.g., processed sensor data). In atleast one example, prediction system 524 can determine featuresassociated with the object based at least in part on the sensor data,the map data, and/or the perception data. As described above, featurescan include an extent of an object (e.g., height, weight, length, etc.),a pose of an object (e.g., x-coordinate, y-coordinate, z-coordinate,pitch, roll, yaw), a velocity of an object, an acceleration of anobject, and a direction of travel of an object (e.g., a heading).Moreover, prediction system 524 may be configured to determine adistance between an object and a proximate driving lane, a width of acurrent driving lane, proximity to a crosswalk, semantic feature(s),interactive feature(s), etc.

Prediction system 524 can analyze features of objects to predict futureactions of the objects. For instance, prediction system 524 can predictlane changes, decelerations, accelerations, turns, changes of direction,or the like. The prediction system 524 can send prediction data todrivable area determination system 528 so that drivable areadetermination system 528 can utilize the prediction data to determinethe boundaries of the drivable area (e.g., based on one or more of anuncertainty in position, velocity, acceleration in addition to, oralternatively, with a semantic classification of the object). Forinstance, if the prediction data indicates that a pedestrian walkingalong the shoulder is behaving erratically, drivable area determinationsystem 528 can determine an increased offset of the drivable areaproximate the pedestrian. In some examples where vehicle 502 is notautonomous, prediction system 524 may provide an indication (e.g., anaudio and/or visual alert) to a driver of a predicted event that mayaffect travel.

In some examples, prediction system 524 can include functionality todetermine predicted point(s) representing predicted location(s) of anobject in the environment. Prediction system 524, in someimplementations, can determine a predicted point associated with a heatmap based at least in part on a cell associated with a highestprobability and/or based at least in part on cost(s) associated withgenerating a predicted trajectory associated with the predicted point.

For example, prediction system 524 can select a point, cell, or regionof a heat map as a predicted point based at least in part on evaluatingone or more cost functions associated with risk factors, safety, andvehicle dynamics, just to name a few examples. Such costs may include,but are not limited to, a positional-based cost (e.g., limiting thedistance allowed between predicted points), a velocity cost (e.g., aconstant velocity cost enforcing a constant velocity through thepredicted trajectory), an acceleration cost (e.g., enforcingacceleration bounds throughout the predicted trajectory), an expectationthat the object may follow rules of the road, and the like. In at leastsome examples, the probability associated with the cell may bemultiplied with the cost (which, in at least some examples, may benormalized) such that the point (e.g., a candidate point) associatedwith the highest value of the cost times probability is selected as thepredicted point associated with an object at a particular time.

In general, planner system 526 can determine a path for vehicle 502 tofollow to traverse through an environment. For example, planner system526 can determine various routes and trajectories and various levels ofdetail. For example, planner system 526 can determine a route to travelfrom a first location (e.g., a current location) to a second location(e.g., a target location). For the purpose of this discussion, a routecan be a sequence of waypoints for travelling between two locations. Asnon-limiting examples, waypoints include streets, intersections, globalpositioning system (GPS) coordinates, etc. Further, planner system 526can generate an instruction for guiding the autonomous vehicle along atleast a portion of the route from the first location to the secondlocation. In at least one example, planner system 526 can determine howto guide the autonomous vehicle from a first waypoint in the sequence ofwaypoints to a second waypoint in the sequence of waypoints. In someexamples, the instruction can be a trajectory, or a portion of atrajectory. In some examples, multiple trajectories can be substantiallysimultaneously generated (e.g., within technical tolerances) inaccordance with a receding horizon technique, wherein one of themultiple trajectories is selected for vehicle 502 to navigate. Thus, inexample implementations described herein, planner system 526 maygenerate trajectories along which the vehicle can navigate, with thetrajectories being contained within the drivable area.

Drivable area determination system 528 is configured to determine adrivable area, such as drivable area 110. Although illustrated as aseparate block in memory 518, in some examples and implementations,drivable area determination system 528 may be a part of planner system526. Drivable area determination system 528 can access sensor data fromsensor system(s) 506, map data from map storage 532, object informationfrom object information store 534, outputs from one or more oflocalization system 520, perception system 522, and/or prediction system524 (e.g., processed data). By way of non-limiting example, drivablearea determination system 528 may access (e.g., retrieve or receive) oneor more planned paths. The planned paths may represent potential pathsto navigate the environment, and may be determined based on map data,object information, and/or perception data, for example. In someexamples, the planned paths may be determined as candidate paths forcarrying out a mission. For instance, vehicle computing device(s) 504,may define or determine a mission as a highest-level of navigation to adestination, e.g., a series of roads for navigating to the destination.Once the mission is determined, one or more actions for carrying outthat high-level navigation may then be determined. Actions may includemore frequent determinations of how to carry out the mission. Forexample, actions may include tasks such as “follow vehicle,” “passvehicle on the right,” or the like. In some examples, the projectedpaths described herein may be determined for each action.

For the planned path(s), drivable area determination system 528 maydetermine, at discrete points along the planned path(s), lateraldistances from the path to objects in the environment. For example, thedistances may be received as perception data generated by perceptionsystem 522, and/or may be determined using mathematical and/or computervision models, such as ray casting techniques. Various lateral distancesmay then be adjusted to account for other factors. For example, it maybe desirable to maintain a minimum distance between vehicle 502 andobjects in the environment. In implementations of this disclosure,information about the objects, including semantic classifications, maybe used to determine those distance adjustments. Moreover, predictionsystem 524 may also provide prediction data about a predicted movementof the objects, and the distances may further be adjusted based on thosepredictions. For example, the prediction data may include a confidencescore and the lateral distance may be adjusted based on the confidencescore, e.g., by making a greater adjustment for less confidentpredictions and slighter or no adjustments for more confidentpredictions. Using the adjusted distances, drivable area determinationsystem 528 may define boundaries of the drivable area. In at least someexamples, the boundaries may be discretized (e.g., every 10 cm, 50 cm, 1m, etc.) and information regarding the boundary may be encoded (e.g.,lateral distance to the nearest object, semantic classification of thenearest object, confidence and/or probability score associated with theboundary, etc.). As described herein, the trajectory determined byplanner system 526 may be confined by, and in accordance with, in thedrivable area. While drivable area determination system 528 isillustrated as being separate from planner system 526, one or more ofthe functionalities of drivable area system 528 may be carried out byplanner system 526. In some embodiments, drivable area determinationsystem 528 may be a part of planner system 526.

In at least one example, localization system 520, perception system 522,prediction system 524, planner system 526, and/or drivable areadetermination system 528 can process sensor data, as described above,and can send their respective outputs over network(s) 536, to computingdevice(s) 538. In at least one example, localization system 520,perception system 522, prediction system 524, and/or planner system 526can send their respective outputs to computing device(s) 538 at aparticular frequency, after a lapse of a predetermined period of time,in near real-time, etc.

In at least one example, vehicle computing device(s) 504 can include oneor more system controllers 530, which can be configured to controlsteering, propulsion, braking, safety, emitters, communication, andother systems of vehicle 502. These system controller(s) 530 cancommunicate with and/or control corresponding systems of drive system(s)514 and/or other components of vehicle 502. For example, systemcontrollers 530 may cause the vehicle to traverse along a drive pathdetermined by planner system 526, e.g., in a drivable area determined bydrivable area determination system 528.

In at least one example, sensor system(s) 506 can include LIDAR sensors,RADAR sensors, ultrasonic transducers, SONAR sensors, location sensors(e.g., GPS, compass, etc.), inertial sensors (e.g., inertial measurementunits, accelerometers, magnetometers, gyroscopes, etc.), cameras (e.g.,RGB, UV, IR, intensity, depth, etc.), microphones, wheel encoders,environment sensors (e.g., temperature sensors, humidity sensors, lightsensors, pressure sensors, etc.), etc. sensor system(s) 506 can includemultiple instances of each of these or other types of sensors. Forinstance, the LIDAR sensors can include individual LIDAR sensors locatedat the corners, front, back, sides, and/or top of vehicle 502. Asanother example, the camera sensors can include multiple camerasdisposed at various locations about the exterior and/or interior ofvehicle 502. sensor system(s) 506 can provide input to vehicle computingdevice(s) 504. Additionally and/or alternatively, sensor system(s) 506can send sensor data, via network(s) 536, to computing device(s) 538 ata particular frequency, after a lapse of a predetermined period of time,in near real-time, etc.

Vehicle 502 can also include one or more emitters 508 for emitting lightand/or sound. emitter(s) 508 in this example include interior audio andvisual emitters to communicate with passengers of vehicle 502. By way ofexample and not limitation, interior emitters can include speakers,lights, signs, display screens, touch screens, haptic emitters (e.g.,vibration and/or force feedback), mechanical actuators (e.g., seatbelttensioners, seat positioners, headrest positioners, etc.), and the like.Emitter(s) 508 in this example also include exterior emitters. By way ofexample and not limitation, the exterior emitters in this exampleinclude light emitters (e.g., indicator lights, signs, light arrays,etc.) to visually communicate with pedestrians, other drivers, othernearby vehicles, etc., one or more audio emitters (e.g., speakers,speaker arrays, horns, etc.) to audibly communicate with pedestrians,other drivers, other nearby vehicles, etc., etc. In at least oneexample, emitter(s) 508 can be disposed at various locations about theexterior and/or interior of vehicle 502.

Vehicle 502 can also include communication connection(s) 510 that enablecommunication between vehicle 502 and other local or remote computingdevice(s). For instance, communication connection(s) 510 can facilitatecommunication with other local computing device(s) on vehicle 502 and/ordrive system(s) 514. Also, communication connection(s) 510 can allow thevehicle to communicate with other nearby computing device(s) (e.g.,other nearby vehicles, traffic signals, etc.). communicationsconnection(s) 510 also enable vehicle 502 to communicate with a remotetele-operations computing device or other remote services.

Communications connection(s) 510 can include physical and/or logicalinterfaces for connecting vehicle computing device(s) 504 to anothercomputing device or a network, such as network(s) 536. For example,communications connection(s) 510 can enable Wi-Fi-based communicationsuch as via frequencies defined by the IEEE 802.11 standards, shortrange wireless frequencies such as BLUETOOTH®, or any suitable wired orwireless communications protocol that enables the respective computingdevice to interface with the other computing device(s).

In at least one example, vehicle 502 can include drive system(s) 514. Insome examples, vehicle 502 can have a single drive system 514. In atleast one example, if vehicle 502 has multiple drive systems 514,individual drive systems 514 can be positioned on opposite ends ofvehicle 502 (e.g., the front and the rear, etc.). In at least oneexample, drive system(s) 514 can include sensor system(s) to detectconditions of drive system(s) 514 and/or surroundings of vehicle 502. Byway of example and not limitation, sensor system(s) 506 can includewheel encoder(s) (e.g., rotary encoders) to sense rotation of the wheelsof the drive module, inertial sensors (e.g., inertial measurement units,accelerometers, gyroscopes, magnetometers, etc.) to measure position andacceleration of the drive module, cameras or other image sensors,ultrasonic sensors to acoustically detect objects in the surroundings ofthe drive module, LIDAR sensors, RADAR sensors, etc. Some sensors, suchas the wheel encoder(s) can be unique to drive system(s) 514. In somecases, the sensor system(s) 506 on drive system(s) 514 can overlap orsupplement corresponding systems of vehicle 502 (e.g., sensor system(s)506).

Drive system(s) 514 can include many of the vehicle systems, including ahigh voltage battery, a motor to propel vehicle 502, an inverter toconvert direct current from the battery into alternating current for useby other vehicle systems, a steering system including a steering motorand steering rack (which can be electric), a braking system includinghydraulic or electric actuators, a suspension system including hydraulicand/or pneumatic components, a stability control system for distributingbrake forces to mitigate loss of traction and maintain control, an HVACsystem, lighting (e.g., lighting such as head/tail lights to illuminatean exterior surrounding of the vehicle), and one or more other systems(e.g., cooling system, safety systems, onboard charging system, otherelectrical components such as a DC/DC converter, a high voltagejunction, a high voltage cable, charging system, charge port, etc.).Additionally, drive system(s) 514 can include a drive module controllerwhich can receive and preprocess data from the sensor system(s) and tocontrol operation of the various vehicle systems. In some examples, thedrive module controller can include processor(s) and memorycommunicatively coupled with the processor(s). The memory can store oneor more modules to perform various functionalities of drive system(s)514. Furthermore, drive system(s) 514 also include communicationconnection(s) that enable communication by the respective drive modulewith other local or remote computing device(s).

As described above, vehicle 502 can send sensor data to computingdevice(s) 538 via network(s) 536. In some examples, vehicle 502 can sendraw sensor data to computing device(s) 538. In other examples, vehicle502 can send processed sensor data and/or representations of sensor datato computing device(s) 538 (e.g., data output from localization system520, perception system 522, prediction system 524, and/or planner system526). In some examples, vehicle 502 can send sensor data to computingdevice(s) 538 at a particular frequency after a lapse of a predeterminedperiod of time, in near real-time, etc.

Computing device(s) 538 can receive sensor data (raw or processed) fromvehicle 502 and/or one or more other vehicles and/or data collectiondevices and can determine a drivable area based on the sensor data andother information. In at least one example, computing device(s) 538 caninclude processor(s) 540 and memory 542 communicatively coupled withprocessor(s) 540. In the illustrated example, memory 542 of computingdevice(s) 538 stores a drivable area determination component 544 whichcan include object information storage 546, for example. In at least oneexample, the object information storage 546 can correspond to the objectinformation storage 534 and/or the object information storage.

Drivable area determination component 544 may correspond to drivablearea determination system 528 described above. For example, drivablearea determination component 544 may process data to determine adrivable area remote from the vehicle. For example, the drivable area(or a preferred drivable area from a plurality of drivable areas) may bedetermined at computing device(s) 538 and transferred back to vehicle502, e.g., via networks 536. Moreover, drivable area determinationcomponent 544 can perform one or more operations as described above andascribed to localization system 520, perception system 522, predictionsystem 524, and/or planner system 526. In at least one example, drivablearea determination component 544 can analyze the sensor data todetermine attributes of objects in the environment to (1) determinewhether such object(s) should be included in a drivable area and (2)configure boundaries of the drivable area. For example, drivable areadetermination component 544 may compare information about objects toclassification information, e.g., stored in object information storage546, to determine whether the object will be impacted by the vehicle,whether the object (or a predicted movement of the object) will impactthe vehicle, and/or the extent to which the object should impact thedrivable area.

Drivable area determination component 544 may also or alternativelyconsider features of objects to characterize the drivable area. Featurescan include an extent of an object (e.g., height, weight, length, etc.),a pose of an object (e.g., x-coordinate, y-coordinate, z-coordinate,pitch, roll, yaw), a velocity of an object, an acceleration of anobject, a direction of travel of an object (e.g., a heading), a distancebetween an object and a proximate driving lane, a semanticclassification of the object (car, pedestrian, bicyclist, etc.), a widthof a current driving lane, proximity to a crosswalk, semanticfeature(s), interactive feature(s), etc. In some examples, at least someof the features (e.g., the extent, the pose, etc.) can be determined bya perception system onboard a sensor data source (e.g., vehicle 502and/or the other vehicle(s) and/or data collection device(s)) and otherof the features can be determined based on such features and/or othersensor data and/or map data associated with a map of the environment. Insome examples, a sample can be broken into one or more shorter periodsof time and features can be determined for each of the shorter periodsof time. The features for the sample can be determined based on atotality of features from each of the shorter periods of time.

Processor(s) 516 of vehicle 502 and processor(s) 540 of computingdevice(s) 538 can be any suitable processor capable of executinginstructions to process data and perform operations as described herein.By way of example and not limitation, processor(s) 516 and 540 cancomprise one or more Central Processing Units (CPUs), GraphicsProcessing Units (GPUs), or any other device or portion of a device thatprocesses electronic data to transform that electronic data into otherelectronic data that can be stored in registers and/or memory. In someexamples, integrated circuits (e.g., ASICs, etc.), gate arrays (e.g.,FPGAs, etc.), and other hardware devices can also be consideredprocessors in so far as they are configured to implement encodedinstructions.

Memory 518 and 542 are examples of non-transitory computer-readablemedia. Memory 518 and 542 can store an operating system and one or moresoftware applications, instructions, programs, and/or data to implementthe methods described herein and the functions attributed to the varioussystems. In various implementations, the memory can be implemented usingany suitable memory technology, such as static random-access memory(SRAM), synchronous dynamic RAM (SDRAM), nonvolatile/Flash-type memory,or any other type of memory capable of storing information. Thearchitectures, systems, and individual elements described herein caninclude many other logical, programmatic, and physical components, ofwhich those shown in the accompanying figures are merely examples thatare related to the discussion herein.

It should be noted that while FIG. 5 is illustrated as a distributedsystem, in alternative examples, components of vehicle 502 can beassociated with computing device(s) 538 and/or components of computingdevice(s) 538 can be associated with vehicle 502. That is, vehicle 502can perform one or more of the functions associated with computingdevice(s) 538, and vice versa. Moreover, although various systems andcomponents are illustrated as being discrete systems, the illustrationsare examples only, and more or fewer discrete systems may perform thevarious functions described herein.

The various techniques described herein can be implemented in thecontext of computer-executable instructions or software, such as programmodules, that are stored in computer-readable storage and executed bythe processor(s) of one or more computers or other devices such as thoseillustrated in the figures. Generally, program modules include routines,programs, objects, components, data structures, etc., and defineoperating logic for performing particular tasks or implement particularabstract data types.

Other architectures can be used to implement the described functionalityand are intended to be within the scope of this disclosure. Furthermore,although specific distributions of responsibilities are defined abovefor purposes of discussion, the various functions and responsibilitiesmight be distributed and divided in different ways, depending oncircumstances.

Similarly, software can be stored and distributed in various ways andusing different means, and the particular software storage and executionconfigurations described above can be varied in many different ways.Thus, software implementing the techniques described above can bedistributed on various types of computer-readable media, not limited tothe forms of memory that are specifically described.

Example Clauses

A. A method comprising: determining a drivable area through anenvironment for a vehicle, wherein the drivable area represents a regionin the environment on which the vehicle may traverse; determining atrajectory within the drivable area for the vehicle to follow; receivingsensor data from a sensor on the vehicle; detecting, based at least inpart on the sensor data, an object in the environment; determining,based at least in part on the sensor data, object parameters associatedwith the object, wherein the object parameters comprise one or more of avelocity, a position, a classification, or an extent; determining, basedat least in part on the object parameters, a modified drivable area;determining, based at least in part on the modified drivable area, thatthe trajectory is invalid; determining, based at least in part ondetermining the trajectory is invalid, a modified trajectory; andcontrolling the vehicle according to the modified trajectory.

B. The method of paragraph A, wherein determining the trajectory isinvalid comprises determining, based at least in part on the modifieddrivable area and the trajectory, a cost, and wherein the cost is basedat least in part on a minimum distance to maintain between the vehicleand the object.

C. The method of paragraph B, further comprising: determining, based atleast in part on the object parameters, a predicted trajectory of theobject, wherein the cost is based at least in part on the predictedtrajectory.

D. The method of any of paragraphs A-C, wherein the object parametersindicate a lane change or merge by the object into a lane occupied bythe vehicle.

E. The method of any of paragraphs A-D, wherein controlling the vehicleaccording to the modified trajectory further comprises: controlling thevehicle to follow the object based at least in part on one or more of arelative velocity of the object or a relative distance to the object.

F. The method of any of paragraphs A-E, wherein the classificationcomprises a car, a bicycle, a motorcycle, or a pedestrian.

G. The method of any of paragraphs A-F, wherein determining that thetrajectory is invalid comprises: determining that the trajectoryintersects or is within a threshold distance of a boundary of themodified drivable area.

H. A vehicle comprising: a sensor disposed on the vehicle; a processor;and a computer-readable media storing instructions executable by theprocessor, wherein the instructions, when executed, cause the processorto perform operations comprising: determining a drivable area for thevehicle; determining, based at least in part on the drivable area, areference trajectory for the vehicle to follow; receiving sensor datafrom the sensor; determining, based at least in part on the sensor data,object parameters of an object in an environment through which thevehicle is traversing; modifying the drivable area, based at least inpart on the sensor data, to generate a modified drivable area;determining, based at least in part on the modified drivable area andthe reference trajectory, whether to modify the reference trajectory;and controlling the vehicle based at least in part on whether to modifythe reference trajectory.

I. The vehicle of paragraph H, wherein the object parameters compriseone or more of a velocity, a position, a classification, or an extent.

J. The vehicle of paragraph I, wherein the classification comprises acar, a bicycle, a motorcycle, or a pedestrian.

K. The vehicle of any of paragraphs H-J, wherein, modifying thereference trajectory comprises: maintaining a relative distance and arelative velocity between the vehicle and the object.

L. The vehicle of any of paragraphs H-K, wherein the operations furthercomprise: determining a predicted trajectory of the object; anddetermining a probability associated with the predicted trajectory,wherein controlling the vehicle is further based at least in part on theprobability associated with the predicted trajectory.

M. The vehicle of paragraphs H-L, wherein the object parameters of theobject indicate a lane change or a merge.

N. The vehicle of paragraphs H-M, wherein the object parameters of theobject indicate a turn at an intersection.

O. The vehicle of paragraphs H-N, wherein the modified drivable area isa first modified drivable area, and wherein the operations furthercomprise: receiving additional sensor data based on a second object;modifying the drivable area, based at least in part on the additionalsensor data, to generate a second modified drivable area; determining,based at least in part on the second modified drivable area and thereference trajectory, a cost; and controlling the vehicle based at leastin part on the cost and the first modified drivable area.

P. A non-transitory computer-readable medium storing instruction that,when executed, cause one or more processors to perform operationscomprising: receiving sensor data from a sensor on the vehicle;determining a drivable area that represents a region in which a vehiclemay traverse; determining a trajectory within the drivable area for thevehicle to follow; determining, based at least in part on the sensordata, an object parameter associated with an object; modifying thedrivable area, based at least in part on the object parameter, togenerate a modified drivable area; determining, based at least in parton the modified drivable area and the trajectory, a cost; anddetermining, based at least in part on the cost, whether to modify thetrajectory.

Q. The non-transitory computer-readable medium of paragraph P, theoperations further comprising: determining a modified trajectory, themodified trajectory comprising a different longitudinal accelerationprofile than the trajectory; and controlling the vehicle according tothe modified trajectory.

R. The non-transitory computer-readable medium of paragraphs P-Q,wherein the object parameter comprises one or more of a velocity, aposition, a classification, or an extent.

S. The non-transitory computer-readable medium of paragraphs P-R,wherein the cost is based at least in part on a distance between thevehicle and a boundary of the modified drivable area, and whereincontrolling the vehicle comprises controlling the vehicle based on anacceleration determined based, at least in part, on a relative distanceor a relative velocity between the vehicle and the object.

T. The non-transitory computer-readable medium of paragraphs P-S, theoperations further comprising: determining that the cost is above athreshold cost; and controlling the vehicle to follow the object.

While the example clauses described above are described with respect toone particular implementation, it should be understood that, in thecontext of this document, the content of the example clauses can also beimplemented via a method, device, system, a computer-readable medium,and/or another implementation.

CONCLUSION

While one or more examples of the techniques described herein have beendescribed, various alterations, additions, permutations and equivalentsthereof are included within the scope of the techniques describedherein.

In the description of examples, reference is made to the accompanyingdrawings that form a part hereof, which show by way of illustrationspecific examples of the claimed subject matter. It is to be understoodthat other examples can be used and that changes or alterations, such asstructural changes, can be made. Such examples, changes or alterationsare not necessarily departures from the scope with respect to theintended claimed subject matter. While the steps herein can be presentedin a certain order, in some cases the ordering can be changed so thatcertain inputs are provided at different times or in a different orderwithout changing the function of the systems and methods described. Thedisclosed procedures could also be executed in different orders.Additionally, various computations described herein need not beperformed in the order disclosed, and other examples using alternativeorderings of the computations could be readily implemented. In additionto being reordered, in some instances, the computations could also bedecomposed into sub-computations with the same results.

What is claimed is:
 1. A method comprising: determining a drivable areathrough an environment for a vehicle, wherein the drivable arearepresents a region in the environment on which the vehicle maytraverse; determining a trajectory within the drivable area for thevehicle to follow; receiving sensor data from a sensor on the vehicle;detecting, based at least in part on the sensor data, an object in theenvironment; determining, based at least in part on the sensor data,object parameters associated with the object, wherein the objectparameters comprise one or more of a velocity, a position, aclassification, or an extent; determining, based at least in part on theobject parameters, a modified drivable area; determining, based at leastin part on the modified drivable area, that the trajectory is invalid;determining, based at least in part on determining the trajectory isinvalid, a modified trajectory; and controlling the vehicle according tothe modified trajectory.
 2. The method of claim 1, wherein determiningthe trajectory is invalid comprises determining, based at least in parton the modified drivable area and the trajectory, a cost, and whereinthe cost is based at least in part on a minimum distance to maintainbetween the vehicle and the object.
 3. The method of claim 2, furthercomprising: determining, based at least in part on the objectparameters, a predicted trajectory of the object, wherein the cost isbased at least in part on the predicted trajectory.
 4. The method ofclaim 1, wherein the object parameters indicate a lane change or mergeby the object into a lane occupied by the vehicle.
 5. The method ofclaim 1, wherein controlling the vehicle according to the modifiedtrajectory further comprises: controlling the vehicle to follow theobject based at least in part on one or more of a relative velocity ofthe object or a relative distance to the object.
 6. The method of claim1, wherein the classification comprises a car, a bicycle, a motorcycle,or a pedestrian.
 7. The method of claim 1, wherein determining that thetrajectory is invalid comprises: determining that the trajectoryintersects or is within a threshold distance of a boundary of themodified drivable area.
 8. A vehicle comprising: a sensor disposed onthe vehicle; a processor; and a computer-readable media storinginstructions executable by the processor, wherein the instructions, whenexecuted, cause the processor to perform operations comprising:determining a drivable area for the vehicle; determining, based at leastin part on the drivable area, a reference trajectory for the vehicle tofollow; receiving sensor data from the sensor; determining, based atleast in part on the sensor data, object parameters of an object in anenvironment through which the vehicle is traversing; modifying thedrivable area, based at least in part on the sensor data, to generate amodified drivable area; determining, based at least in part on themodified drivable area and the reference trajectory, whether to modifythe reference trajectory; and controlling the vehicle based at least inpart on whether to modify the reference trajectory.
 9. The vehicle ofclaim 8, wherein the object parameters comprise one or more of avelocity, a position, a classification, or an extent.
 10. The vehicle ofclaim 9, wherein the classification comprises a car, a bicycle, amotorcycle, or a pedestrian.
 11. The vehicle of claim 8, wherein,modifying the reference trajectory comprises: maintaining a relativedistance and a relative velocity between the vehicle and the object. 12.The vehicle of claim 8, wherein the operations further comprise:determining a predicted trajectory of the object; and determining aprobability associated with the predicted trajectory, whereincontrolling the vehicle is further based at least in part on theprobability associated with the predicted trajectory.
 13. The vehicle ofclaim 8, wherein the object parameters of the object indicate a lanechange or a merge.
 14. The vehicle of claim 8, wherein the objectparameters of the object indicate a turn at an intersection.
 15. Thevehicle of claim 8, wherein the modified drivable area is a firstmodified drivable area, and wherein the operations further comprise:receiving additional sensor data based on a second object; modifying thedrivable area, based at least in part on the additional sensor data, togenerate a second modified drivable area; determining, based at least inpart on the second modified drivable area and the reference trajectory,a cost; and controlling the vehicle based at least in part on the costand the first modified drivable area.
 16. A non-transitorycomputer-readable medium storing instruction that, when executed, causeone or more processors to perform operations comprising: receivingsensor data from a sensor on the vehicle; determining a drivable areathat represents a region in which a vehicle may traverse; determining atrajectory within the drivable area for the vehicle to follow;determining, based at least in part on the sensor data, an objectparameter associated with an object; modifying the drivable area, basedat least in part on the object parameter, to generate a modifieddrivable area; determining, based at least in part on the modifieddrivable area and the trajectory, a cost; and determining, based atleast in part on the cost, whether to modify the trajectory.
 17. Thenon-transitory computer-readable medium of claim 16, the operationsfurther comprising: determining a modified trajectory, the modifiedtrajectory comprising a different longitudinal acceleration profile thanthe trajectory; and controlling the vehicle according to the modifiedtrajectory.
 18. The non-transitory computer-readable medium of claim 16,wherein the object parameter comprises one or more of a velocity, aposition, a classification, or an extent.
 19. The non-transitorycomputer-readable medium of claim 16, wherein the cost is based at leastin part on a distance between the vehicle and a boundary of the modifieddrivable area, and wherein controlling the vehicle comprises controllingthe vehicle based on an acceleration determined based, at least in part,on a relative distance or a relative velocity between the vehicle andthe object.
 20. The non-transitory computer-readable medium of claim 16,the operations further comprising: determining that the cost is above athreshold cost; and controlling the vehicle to follow the object.